Aeroplane



w. n. BOHLANDER.

AEROPLANE. APPLICATION FILED MAR. 1,4919.

1,355,751 Patented Oct. 12,1920.

2 SHEETS-SHEET I.

-.722 den lbrx wwd W. R. BOHLANDER.

' 'AEROPLAN'E.

APPLICATION FILED MAR. l, 1919.

1,355,751, I Patented Oct. 12,1920.

2 SHEETSSHEET 2.

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IZWILBURR. BOHLANDER, Dame oHIo.

AEROILANE.

Specification of Letters Patent.

Patented Oct. 12, 1920.

Application filed March 1, 1919. Serial No. 280,016.

To all whom it may concern:

Be it known that I, WILBUR R; BOHLAN- DER, a citizen of the United States, and a resident of Piqua, in the county of Miami and State of Ohio,have invented certain new and useful Improvements in Aeroplanes, of which the following is a full, clear, .and exact description, reference being made to the accompanying drawings, forming part of this specification.

My invention. relates to aeroplanes, and has as its object the stabilizing of such planes against tipping and dipping. This ob ect I accomplish bylthat certain construction and arrangement of parts to be hereinafter more specifically pointed out and claimed, wherein the stabilization is accomplished chiefly by creating counter air currents and utilizing the tendency of the plane to compress the air beneath it as the agent for establishing'the stability. By thls compression, I refer to the necessary result of the heavier-than-air machine moving through the air. w

In the drawings,

Figure 1 is a top plan view of a biplane illustrating my invention.

Fig. 2 is a front elevation of the plane.

Fig. 3 is a side elevation thereof.

Fig. 4 is a side elevation of a plane on a smaller scale, with air currents or lines of resistance illustrated by lines and arrows.

Fig. 5 is a front elevation with the air depicted in the same manner as in Fig. 4.

The aeroplane shown is a biplane, having the lower plane 1, the upper plane 2, and the braces 3. The plane has the body indicated at 4 and the rudder at 5. My invention resides in the construction of the upper plane and in the provision of two stabilizers located at each end of the lower plane.

Taking up first the stabilizers :-they are alike in construction for both sides, and have frames 6 of rectangular shape'and as long as the width of the lower plane, said frames being located at the tips of the lower plane so as to lie under the overhang of the upper plane. This position would naturally vary with the make of plane, and the number of planes employed.

The stabilizer frames are covered with suitable cloth on the outer side-7 and the top 8. They are uncovered except along these two sides. The operation of the stabilizer is shown in Fig. 5.

For convenience, the currents of air striklaterally on the aeroplane are illustrated bythe lines m, g and 2 (each line having arrows thereon to indicate its direction). The 7 current w in striking the right tip of the upper plane (the-left in the drawingywill tend to tip the craft to the left. The current y will not affect the tipping appreciably,

and the current a, if no stabilizer were present would not be able'to' counteract the tipping pressure of the current 00 by pressure on the lefttip ofthe upper plane. I

d When the current e strikes the stabilizer, however, the air will be forced around from the side 7 to the side 8, which will exert a strong lifting tendency on the left side of the frame intermediate the planes, acting' almost at right angles to the horizontal axis of the craft. The down pressure of the machine will add to thcpressureof the current 2 and thus give it additional effect in counteracting the current a which has the advantage of larger wing surface over current e. It can also be observed that the stabilizers function for currents of air coming from the same direction as the tipping current, and that chance currents of air from the tipped end of the craft will be prevented from affecting the tipped-up stabilizer by the interposition of the lower plane-in the path of the current.

The upper plane 2 is constructed with the long opening or open space 9 which runs substantially the whole width of the plane. The effect which this opening will have is illustrated in Fig. 4, where the variouscurrents into which a craft could run are intended to be depicted.-

-lVhen the current a strikes the lower plane there is a tendency to lift the craft, but not to cause it suddenly to dip or take a perpendicular dive. The currents which tend to lift the nose of the craft-upwardly are those which strike the front part of the upper plane from below. indicated at c, and those which strike the rear part of the upper plane from above marked 6. Those which tend to cause dipping down of the nose, are the currents which strike the rear urrents running horiupwardly through the opening and will there be met by the horizontal current 9 and the downward currents e and f, if encountered by the craft. The result of the downward and parallel currents striking the current 0 will be to bend it back as shown at 0 ""against the rear of the plane 2' and tend to depress the said rear portion. The

current at 9 which is'naturally very" strong a'sit directly opposes: the movement ofthe craft,,is the chief agent in the turning back of the current a t-0' andthe current at 0 counteracts the current 1).

It should be understood that the currents selected are merely, representative of cu-r-' rents'acting against the plane from all sources, and that there would be different but similar I results for different currents.

- \Vhen the craft starts to tilt nose first, there would always be the currents g andcurrents 0a In addition there would be some one of the danger currents band f. Ordinarily thecurrent a will be the; prevailing current which'strikes the craft, since it flies with the nose tilted up in order not to fall by gravity, and the'diverting of part ofthis current to the top of the rear of the upper plane is the stabilizing feature against dipping or diving.' r v The invention thus provides for the aero'-' plane a tendency to remain what might be called even keel in the air, and'to right itself against sudden tipping or dipping.

The principle utilized for accomplishing the purpose might be stated as the changing of direction of the a1r currents or pressure againstthe under surfaces of the planes or I stabilizers, so as to develop a counter tendency to' dangerous currents. The-means used "are the preferred ones as applied toa f biplane of the type more or less' diagrammatically indicated in the drawings.

" 'Having-thus-described my invention, what' I claim as new anddesire to secure by Letters Patent, is v J 1. In an aeroplane composed of two or more planes, means for stabil zing the craft against -sideward' tipplng, comprislng auxiliary frames mounted on each end of the i lower plane underneath the endsof'the upper'plane and'having perpendicular sur- 7 faces for redirecting upward, currents and lateral surfaceswhich receive'the redirected" currents in a lifting direction, i, 2. In- 'an aeroplane composed of two or more planes, means forstabilizing the craft against sideward tipping, comprising auxiliaryframes of rectangular shape and mounted at'the' tips of ,thes'lower plane g frame having an o'utside covering and -a top underneath the upper'plane, the auxiliary covering, the outside coveringacting to re? direct upward slanting air currents and turn them directlyup against'the top covering v andthence underneathjthe upper plane, for thepurpose described, V 3'. In an aeroplane composed of'two' or more planes, means for stabilizing the craft WiLBcR'R; Boat-Alanna; 

